A Study on the Rod Type Ultrasonic Motor

2013 ◽  
Vol 716 ◽  
pp. 600-607 ◽  
Author(s):  
Jwo Ming Jou
Keyword(s):  
Rotational Speed ◽  
High Speed ◽  
Mechanical Systems ◽  
Ultrasonic Motor ◽  
Experimental Results ◽  
High Loading ◽  
Optical Lens ◽  
Maximum Loading ◽  
High Torque ◽  
Low Torque

This study is to explore a rod type ultrasonic motor, it can solve the traditional ultrasonic motor with a high speed, but only low torque (or low loading ability) the shortcomings. Or want to improve the traditional ultrasonic motor with high torque (or high loading ability), but speed is too low the drawback. In other words, this study is expected to perform the ultrasonic motor, hope that we can have both higher speed and higher torque of the effect (or higher loading ability), and it can be applied to drive the optical lens (or electro-mechanical systems ) or applied to toggle the slider (or linear rails ). Based on the experimental results, we found that maximum rotational speed is 200rpm under conditions of 180Vp-p, 33.7kHz and 53gw preload. And the maximum loading ability and torque is respectively 4.13kgw and 0.273Nm under conditions of 180Vp-p, 33.7kHz and 15rpm rotational speed. Under similar size and driving conditions, its rotational speed is 3.8 times that of the conventional ultrasonic motor and the loading ability is 7.0 times the conventional ultrasonic motor.

Experimental study on frictional loss of high-speed bearings based on free-deceleration and energy-balance methods

2019 ◽  
Vol 71 (4) ◽  
pp. 509-514 ◽  
Author(s):  
Shengli Tian ◽  
Xiaoan Chen ◽  
Tianchi Chen ◽  
Ye He
Keyword(s):  
Energy Balance ◽  
Rotational Speed ◽  
High Speed ◽  
Mechanical Systems ◽  
Coupling Factor ◽  
Thermomechanical Coupling ◽  
Frictional Torque ◽  
Frictional Loss ◽  
Content Type ◽  
Relationship Of

Purpose The purpose of this study is to investigate accurate and effective experimental methods for measuring the frictional loss of bearings (FLB) in mechanical systems and to measure the effect of various operating parameters on the frictional loss of high-speed mechanical systems. Design/methodology/approach Two novel methods were studied in this paper to measure the FLB: the free-deceleration method and the energy-balance method. A special high-speed motorised spindle and a friction loss test rig were designed and built to measure the effects of rotational speed, lubrication, preload and operating temperature on the FLB. Findings The experimental results showed that the frictional torque of bearings increases initially but then decreases with an increase in rotational speed. Similarly, the FLB decreases initially and then increases with an increase in temperature because of the influence of the viscosity–temperature relationship of the lubricant and the thermomechanical coupling factor. The optimal lubricant flow was determined, and the effectiveness of a novel preload online adjusting device was verified through experiments. Originality/value The research results of this paper provide the basis and methods for the measurement, reduction and prediction of the FLB in mechanical systems.

Design of Torque Balancing Cams for Globoidal Cam Indexing Mechanisms

2002 ◽  
Vol 124 (3) ◽  
pp. 441-447 ◽  
Author(s):  
Der Min Tsay ◽  
Hui Chun Ho ◽  
Kuan Chang Wang
Keyword(s):  
Rotational Speed ◽  
High Speed ◽  
Experimental Results ◽  
B Splines ◽  
Input Shaft ◽  
Tbc Systems

A technique for designing torque balancing cam (TBC) systems that are composed of spring-loaded planar cams with translating followers for globoidal cam indexing mechanisms (GCIMs) has been presented. Such a device can be attached to the input shaft of a GCIM to reduce the variation of its cam rotational speed. As a result, for high-speed applications, the intensity of residual vibrations of a GCIM can be decreased and its indexing accuracy can be improved. To approximate the required counterbalancing torque curves, nonparametric rational B-splines have been applied to synthesize the planar cam motion programs. Experimental results have also been shown to illustrate a practical, high-speed application. It has been proven that the use of such a TBC mechanism is useful and effective.

Effects of Miniaturisation on Electromagnetic Motors for Micro Mechatronic Systems

2010 ◽  
Author(s):  
Samir Mekid
Keyword(s):  
Rotational Motion ◽  
Rotational Speed ◽  
High Speed ◽  
Full Potential ◽  
Mechatronic Systems ◽  
General Behaviour ◽  
Dc Motors ◽  
High Torque ◽  
Scaling Down ◽  
Very High

This paper explores the possibilities and the limitations of scaling down DC motors needed for micro mechatronic systems. It is observed that power and torque decrease with the volume of the motor i.e. diameter and length. Hence producing powerful micro-motors with high torque is currently not possible with direct miniaturisation. Alternative ways of improving the performance are crucial. Background discussion is suggested in this paper. Yet, rotational speed increases when the motors become smaller. They can reach very high speed ranges (in the order of 100,000 rpm) due to the reduction in inertia and friction but with lower torques though. A general behaviour trend between the motor size and its characteristics are discussed. It is expected in order to reach the full potential of micro motors that innovative principles should be considered to generate rotational motion suitable for miniaturisation.

Energy saving analysis of the hydrostatic drives used in the rotary head system of the blast hole drill rig

2019 ◽  
Vol 233 (5) ◽  
pp. 1086-1097
Author(s):  
Alok Vardhan
Keyword(s):  
Energy Saving ◽  
High Speed ◽  
Blast Hole ◽  
Open Pit ◽  
Hole Drilling ◽  
Drill Bit ◽  
Low Speed ◽  
Displacement Pump ◽  
High Torque ◽  
Low Torque

Blast hole drill rigs are used for drilling the soft and the medium-hard rocks in open-pit mines. In such rigs, the drill bit is rotated by a hydrostatic drive. In this respect, two different type hydrostatic drives have been considered. In the first drive, the rotation of the drill bit takes place by a variable displacement pump and two low-torque high-speed hydro-motors along with a step-down gear unit (i.e. LTHS drive), whereas in the second drive an identical pump and a high-torque low-speed hydro-motor (i.e. HTLS drive) rotate the drill bit. In this study, the energy saving analysis of the above mentioned hydrostatic drives has been performed with respect to the load profile of the blast hole drilling. In this respect, the modelling, simulation and the experimentation of the drives have been carried out. Simulations have been performed in MATLAB–Simulink environment and it has been verified through experiments. The proportional-integral-derivative control algorithm has been used to control the drives speed in various loading stages. Results show that the high-torque low-speed drive save more energy compares to the low-torque high-speed drive for the usual operating range of the blast hole drilling.

scholarly journals Automated Design and Analysis of a Variable Displacement Linkage Motor

2019 ◽  
Author(s):  
Nathaniel J. Fulbright ◽  
Grey C. Boyce-Erickson ◽  
Thomas R. Chase ◽  
Perry Y. Li ◽  
James D. Van de Ven
Keyword(s):  
High Speed ◽  
Solution Space ◽  
Torque Ripple ◽  
Automated Method ◽  
Motor Design ◽  
Displacement Pump ◽  
Variable Displacement ◽  
High Torque ◽  
Low Torque ◽  
Axial Piston

Abstract Hydrostatic drives consisting of a variable displacement pump and a low speed high torque (LSHT) motor are frequently used in off-highway vehicles. A variable displacement traction motor is desirable because of the ability to downsize the pump and thereby run the hydrostat at higher efficiency, as well as the possibility of hybridization of the drivetrain. Currently on the market are fixed and discrete speed LSHT radial piston motors and high speed low torque variable displacement axial piston motors. The radial piston motors are displacement dense but are not continuously variable, whereas the axial piston motors are continuously variable but require gearboxes, introducing packaging and robustness concerns. The Variable Displacement Linkage Motor (VDLM) is a LSHT motor that is continuously variable. It offers several benefits over current LSHT motors in that it is highly efficient over its operating range, it has low torque ripple, and it is displacement dense due to its multi-lobed cam and radial packaging. As with the design of any motor, the process is iterative and must be performed whenever performance objectives change. This paper describes an automated method for rapid exploration of the solution space for a variable displacement motor with specific application to the VDLM. This method leads to a motor design that theoretically can achieve 97% efficiency with a torque ripple below 5% at full displacement.

Yaw Galloping of a TLWP Platform Under High Speed Currents by Analytical Methods and its Comparison With Experimental Results

2017 ◽  
Author(s):  
Francisco Lamas ◽  
Miguel A. M. Ramirez ◽  
Antonio Carlos Fernandes
Keyword(s):  
High Speed ◽  
Production Systems ◽  
Experimental Tests ◽  
Experimental Results ◽  
Analytical Methodology ◽  
New Approach ◽  
Laboratory Facilities ◽  
Polynomial Curve ◽  
Computational Fluid Dynamics Cfd ◽  
Cfd Analyses

Flow Induced Motions are always an important subject during both design and operational phases of an offshore platform life. These motions could significantly affect the performance of the platform, including its mooring and oil production systems. These kind of analyses are performed using basically two different approaches: experimental tests with reduced models and, more recently, with Computational Fluid Dynamics (CFD) dynamic analysis. The main objective of this work is to present a new approach, based on an analytical methodology using static CFD analyses to estimate the response on yaw motions of a Tension Leg Wellhead Platform on one of the several types of motions that can be classified as flow-induced motions, known as galloping. The first step is to review the equations that govern the yaw motions of an ocean platform when subjected to currents from different angles of attack. The yaw moment coefficients will be obtained using CFD steady-state analysis, on which the yaw moments will be calculated for several angles of attack, placed around the central angle where the analysis is being carried out. Having the force coefficients plotted against the angle values, we can adjust a polynomial curve around each analysis point in order to evaluate the amplitude of the yaw motion using a limit cycle approach. Other properties of the system which are flow-dependent, such as damping and added mass, will also be estimated using CFD. The last part of this work consists in comparing the analytical results with experimental results obtained at the LOC/COPPE-UFRJ laboratory facilities.

The Effect of Strain Rate on the Material Characteristics of Nickel-Based Superalloy Inconel 718

2007 ◽  
Vol 340-341 ◽  
pp. 283-288 ◽  
Author(s):  
Jung Han Song ◽  
Hoon Huh
Keyword(s):  
Dynamic Response ◽  
High Strain Rate ◽  
Strain Rate ◽  
Turbine Blade ◽  
Inconel 718 ◽  
High Speed ◽  
High Strain ◽  
Split Hopkinson Pressure Bar ◽  
Experimental Results ◽  
Stress Wave Propagation

The dynamic response of the turbine blade materials is indispensable for analysis of erosions of turbine blades as a result of impulsive loading associated with gas flow. This paper is concerned with the dynamic material properties of the Inconel 718 alloy which is widely used in the high speed turbine blade. The dynamic response at the corresponding level of the strain rate should be acquired with an adequate experimental technique and apparatus due to the inertia effect and the stress wave propagation. In this paper, the dynamic response of the Inconel 718 at the intermediate strain rate ranged from 1/s to 400/s is obtained from the high speed tensile test and that at the high strain rate above 1000/s is obtained from the split Hopkinson pressure bar test. The effects of the strain rate on the dynamic flow stress, the strain rate sensitivity and the failure elongation are evaluated with the experimental results. Experimental results from both the quasi-static and the high strain rate up to 3000/s are interpolated in order to construct the constitutive relation that should be applied to simulate the dynamic behavior of the turbine blade made of the Inconel 718.

scholarly journals Optimization of Air Gap Length and Capacitive Auxiliary Winding in Three-Phase Induction Motors Based on a Genetic Algorithm

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4407
Author(s):  
Mbika Muteba
Keyword(s):  
Genetic Algorithm ◽  
Design Process ◽  
Power Factor ◽  
High Speed ◽  
High Efficiency ◽  
Air Gap ◽  
Element Analysis ◽  
Three Phase ◽  
High Torque ◽  
Cage Induction Motor

There is a necessity to design a three-phase squirrel cage induction motor (SCIM) for high-speed applications with a larger air gap length in order to limit the distortion of air gap flux density, the thermal expansion of stator and rotor teeth, centrifugal forces, and the magnetic pull. To that effect, a larger air gap length lowers the power factor, efficiency, and torque density of a three-phase SCIM. This should inform motor design engineers to take special care during the design process of a three-phase SCIM by selecting an air gap length that will provide optimal performance. This paper presents an approach that would assist with the selection of an optimal air gap length (OAL) and optimal capacitive auxiliary stator winding (OCASW) configuration for a high torque per ampere (TPA) three-phase SCIM. A genetic algorithm (GA) assisted by finite element analysis (FEA) is used in the design process to determine the OAL and OCASW required to obtain a high torque per ampere without compromising the merit of achieving an excellent power factor and high efficiency for a three-phase SCIM. The performance of the optimized three-phase SCIM is compared to unoptimized machines. The results obtained from FEA are validated through experimental measurements. Owing to the penalty functions related to the value of objective and constraint functions introduced in the genetic algorithm model, both the FEA and experimental results provide evidence that an enhanced torque per ampere three-phase SCIM can be realized for a large OAL and OCASW with high efficiency and an excellent power factor in different working conditions.

scholarly journals Operating temperatures of oil-lubricated medium-speed gears: Numerical models and experimental results

2003 ◽  
Vol 217 (2) ◽  
pp. 87-106 ◽  
Author(s):  
H Long ◽  
A A Lord ◽  
D T Gethin ◽  
B J Roylance
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Surface Temperature ◽  
Rotational Speed ◽  
High Speed ◽  
Applied Load ◽  
Frictional Heat ◽  
Transfer Coefficients ◽  
Gear Teeth ◽  
Heat Transfer Coefficients

This paper investigates the effects of gear geometry, rotational speed and applied load, as well as lubrication conditions on surface temperature of high-speed gear teeth. The analytical approach and procedure for estimating frictional heat flux and heat transfer coefficients of gear teeth in high-speed operational conditions was developed and accounts for the effect of oil mist as a cooling medium. Numerical simulations of tooth temperature based on finite element analysis were established to investigate temperature distributions and variations over a range of applied load and rotational speed, which compared well with experimental measurements. A sensitivity analysis of surface temperature to gear configuration, frictional heat flux, heat transfer coefficients, and oil and ambient temperatures was conducted and the major parameters influencing surface temperature were evaluated.

Sign in / Sign up

Export Citation Format

Share Document